Mississippi State University (MSU) is ranked by the Carnegie Foundation for the Advancement of Teaching as a very high research activity university. MSU is the only school in the state with this distinction, and one of only 108 nationwide. In FY 2013, the university secured $114 million in external research funding. Mississippi State University maintains a single core, AAALAC accredited, laboratory animal (rodent/rabbit) housing facility located within the College of Veterinary Medicine (CVM). This facility services the biomedical research needs of both CVM and MSU. The 1985-era facility is not utilized at peak capacity but does provide animal housing and techniques space to meet the needs of 18 researchers who are either agency or internally funded. A single, 28 year old, air handling unit (AHU) provides the mechanical basis for ensuring Guide for the Care and Use of Laboratory Animals (Guide) compliant environmental conditions for research animals housed in this facility. The AHU is at the end of its functional lifespan. Analyses of air changes/hour, temperature and humidity levels show frequent straying from set points and regulatory ranges. Equipment funded by this proposal will provide the necessary and required indoor environmental standards for research animals.